Door lock for elevators



Sept. 25, 1923. H 1,468,678 J. T. SCHLESINGER I DOOR LOCK FOR ELEVATORS Filed May 17 1921 ATTORNEY Patented Sept. 25, 1923.

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JOSEPH T.- SOHLESI1\TGER-, OF NEW YORK, N. Y., ASSIGNOR, BY MESNE ASSIGNMENTS,

TO UTILITY SAFETY APPLIANCE CORPORATION.

DOOR LOCK IEORELEVATORS.

Application filed May 17, 1921. Serial No. 170,458.

To all whom 2'25 may concern:

Be it known that I, Josnrrr T. SoHLEs- INGER, a citizen of Hungary, and resident of the city of New York, in the county of New York and State of New York, have invented certain new and useful Improvements in Door Locks for Elevators, of which the following is a specification.

The oresent invention relates to im rove-' ments in door-locks for elevators, and more particularly to ,a door-lock which controls,

by the position of the door, the elevator motor mechanism.

The main object of the invention is to provide a simple and efficient door actuated control mechanism for elevators, involving elec tric features.

Another object of the invention is to produce a simple and inexpensive door-lock for elevators, including a stationary element on the door. frame and a movable element on the door, said stationary and movable elements constituting a switch inserted into the I control circuit of the motor, so that the elevator cannot be started unless the door is in its fully closed and locked position, said movable element being actuated by manually operated means when the door is to be opened, but automatically operated when the door is being closed.

With these and other objects in view, which will more fully appear as the nature of the invention is better understood, the same consists in the combination, arrangement and construction ofparts hereinafter described, pointed out in the appended claims and illustrated in the accompanying drawings, it being understood that many changes may be made in the size and proportion of the several parts and details of construction within the scope of the appended claims, without departing from the spirit -or sacrificing any of the advantages of the invention.

One of the many possible embodiments of the invention is illustrated in the accompanying drawings, in which Figure 1is a front elevation, partly in section, of a door-lock constructed in accordance with the present invention, the cover of its lock-casing being removed in order to show the interior construction; Fig. 2 is a side elevation thereof; and Fig. 3 is a sec- 1310111 taken on line 3-3 of Fig. 1, on a larger sea 9. i

In the drawings, the numeral 10 indicates a casing of any suitable construction, adapted to be fastened to the door frame of an elevator, for instance, by screws passing through lugs 11 thereon. This casing is provided with a detachable front plate, not shown in the drawings. In the side 12 of the casing is formed an opening 13, through which a latch 14, pivoted at 15 to the elevator door, may be projected into the casing. Below the opening 13 there is mounted within the casing an insulating block 16 to which are fastened, for instance by screws 17, the spaced apart stationary contact points 18 of a switch. Each of these contact points is, preferably, made in the form of two juxtaposed blade springs, which are held in place by the screws 17, the said contact points being inserted into the motor control circuit of the elevator, conductors leading to the screws 17, in contact with the said contact points.

The latch bolt 14 is adapted to swing by gravity around its pivot 15, it vided on its free end with a downwardly extending projection 19, engaging the inner face of the casing side 12 below the opening 13, when disposed within the said casing. The free end of the latch bolt is rounded, as shown at 20, for engagement with the slanting edge 21 of the opening 13, when the latch bolt is moved toward closing position, the said latch bolt being thereby caused to swing upwards around its pivot 15, dropbeing prois wholly disposed within the lock casing.

On the projection 19 of thelatch bolt is mounted an insulating block 22, carrying a metallic plate 23, which is adapted to bridge the gap between the stationary contact points 18 of the switch. The metallic plate 23 constitutes thus the knife member of a knife switch.

For actuating the latch bolt, there is pivotedat 24 to the elevator door a bellcrank lever 25. one arm of which constitutes an operatng handle 26, while its'other arm is connected by a pivot pin 27 with one end of a link 28. The other end of the said link is provided with a longitudinal slot 29, in engagement with a pin 30 on thelatch bolt 14. The pin 30 is disposed intermedate the ends of the said bolt. The link 28 also carries a pin, denoted by the numeral 31, in goptact with the under face of the latch gap between the stationary contact points 18, thereby completing the motor control circuit. The projection 19 on the latch bolt is in engagement with the inner face of the side 12 of the casing, thereby holding the; door in locked position. The latch bolt has thus a two-fold function, to wit: It, first,

7 serves as a locking bolt and, second, it performsthe function of the knife member of a switch, or in other words it constitutes the movable element of a switch. In order to open the door, the operating handle must be shifted in the direction of the arrow shown' in Fig. 1 of the drawings, whereby by a corresponding movement of the pin 31 on the link 28 causes'the' latch bolt to swing around its pivot into the position shown in dotted lines in Fig. 1 of thedrawings. The door may thusvbe opened by shifting it to the left;' WVhen the latch bolt swings around its pivot in the manner indicated, the

. motor control circuit is opened, so that the lock casing.

elevator cannot be started until the door is again closed and'securely locked. In shifting the door toward closing position, the operator need not actuate the operating handle 26, as the latch bolt will be automatically swung upwards around its pivot when its rounded end 20 comes into contact with the slanting edge 21 of the opening 18 in the As soon as the projection 19 of the latch bolt is disposed wholly within the casing, it drops by gravity, whereby its switch member is automatically brought into engagement with the contact points 18, thus completing the motor control circuit. From this it appears that in closing the door, only the latch bolt is shifted around I its pivot 15, theslot 29 permitting of .such

movement with the link 28 and bellcrank lever 25 in the positions shown in full lines side 12 of the lock casing an opening 13,

the latch bolt. link 28 and bellcrank lever 25 being reversible, that is to say adapted for use in connection with the opening in either side of the lock casing.

What I claim is i '1. In a door-lock for elevators, the com bination with a casing having an opening 1n one of its sides mounted upon the door frame, of a latch bolt pivoted to the elevator ;door,' sp'aced apart contact plates within said casing in the motor control circuit of the elevator, a metallic plate carried by said latch bolt for bridging 'the gap between said contact plates, means for causing' said bolt to swing around its pivot for disengaging said metallic plate from said contact plates, andco-acting means on said bolt and casing causing a similar swinging movement of said bolt around saidpivot 7 when the door is shifted to closing'pos'ition, said latch bolt being actuated by gravity to complete the motor control circuit' within said casing in the motor control'cin. cuit of the elevator, an electricconductor carried by said latch bolt forbridging the a gap between said contact plates, and co-act' ing means on said bolt and casing for swing: mg said bolt around its p1vot so as to bring its locking end in registry with the opening in said casing when the door is shifted to closing position, said latch bolt being actuated by gravity to complete the motor control circuit when the conductor thereon is disposed-wholly within said casing.

3. A door-lock for elevators, the combination with a casing having an opening in one of its sides mounted upon the door frame, of a latch bolt'pivoted'to the elevator door, a projection'on said bolt forengagement with the inner face of said casing below said opening so as to lock the door, spaced apart contact plates within said casing in the motor control circuit of the elevator, an electric conductor'upon said PlOjGCtlOIl for bridging the gap between said contact plates, and co-actmg means on said bolt and casing for swinging said bolt around its pivot so as to bring its projec-i tion in registry with the opening in said casing when the door is shifted to closing position, said. latch bolt dropping by gravity when said projection is disposed wholly within the casing, whereby the electric conductor thereon is automatically brought into engagement with said Contact; plates. Signed at New York, in the county of New York and State ofNew' York, this 19th day of February A. D. 1921.

JosnPH rsoHLEsIueEB. 

